﻿using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class Main: System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            Session.RemoveAll();
            Session.Clear();
        }

        Session["CheckCode"] = "1234";
        txtCheckCode.Value = "1234";        
    }
}